Greek Yogurt and 12 Weeks of Exercise Training on Strength, Muscle Thickness and Body Composition in Lean, Untrained, University-Aged Males

Abstract

Milk and/or whey protein plus resistance exercise (RT) increase strength and muscle size, and optimize body composition in adult males and females. Greek yogurt (GY) contains similar muscle-supporting nutrients as milk yet it is different in several ways including being a semi-solid food, containing bacterial cultures and having a higher protein content (mostly casein) per serving. GY has yet to be investigated in the context of a RT program. The purpose of this study was to assess the effects of GY consumption plus RT on strength, muscle thickness and body composition in lean, untrained, university-aged males. Thirty untrained, university-aged (20.6 ± 2.2 years) males were randomized to 2 groups ( n = 15/group): fat-free, plain GY or a Placebo Pudding (PP; isoenergetic carbohydrate-based pudding) and underwent a combined RT/plyometric training program 3 days/week for 12 weeks. They consumed either GY (20 g protein/dose) or PP (0 g protein/dose) daily, 3 times on training days and 2 times on non-training days. After 12 weeks, both groups significantly increased strength, muscle thickness and fat-free mass (FFM) ( p < 0.05). The GY group gained more total strength (GY; 98 ± 37 kg, PP; 57 ± 15 kg), more biceps brachii muscular thickness (GY; 0.46 ± 0.3 cm, PP; 0.12 ± 0.2 cm), more FFM (GY; 2.4 ± 1.5 kg, PP; 1.3 ± 1.3 kg), and reduced % body fat (GY; −1.1 ± 2.2%, PP; 0.1 ± 2.6%) than PP group ( p < 0.05 expressed as absolute change). Thus, consumption of GY during a training program resulted in improved strength, muscle thickness and body composition over a carbohydrate-based placebo. Given the results of our study, the general benefits of consuming GY and its distinctiveness from milk, GY can be a plausible, post-exercise, nutrient-rich alternative for positive strength, muscle, and body composition adaptations.

Consumption of Greek yogurt during 12 weeks of high-impact loading exercise increases bone formation in young, adult males – a secondary analysis from a randomized trial

“…Although participants (and their trainers) could not be blinded to treatment allocation, contents of the PP were concealed, and it was termed the "study-designed supplement". Further study details and results from our strength, muscular thickness, and body composition outcomes have been published elsewhere (Bridge et al 2019).…”

“…The control group consumed 47 g of a CHO-based PP, which was mixed with water and made to be isoenergetic and chocolate-flavoured (ϳ110 kcals, 0 g protein, 28 g CHO, trace minerals from water) at the same timepoints. Additional details regarding the study foods and timing of intakes have been published elsewhere (Bridge et al 2019). All participants were provided with nutritional guidance to help them compensate for the added energy consumed from the study foods.…”

“…All training sessions were facilitated by a study trainer. Further details regarding the training protocol have been published elsewhere (Bridge et al 2019).…”

“…Dietary data were inputted and analyzed using the ESHA diet analysis program (Food Processor; ESHA Inc., Salem, Ore., USA). Additional information regarding the dietary analysis has been published elsewhere (Bridge et al 2019).…”

“…The analysis of bone markers in this study represent secondary outcomes. The primary outcome from this study (body composition) has been previously published demonstrating that the consumption of GY significantly increased lean mass as well as muscular strength and biceps muscle thickness compared with the carbohydrate placebo (Bridge et al 2019).…”